Development of Experimental System for maneuverability of High-Speed Craft Using an Unmanned Towing Carriage

对硬质刨削船体操纵性的研究非常有限，还没有建立起模拟其操纵特性的理论或实验方法。虽然与常规排水船不同的最重要的特征似乎是航行姿态的改变对操纵的显著影响，但据作者所知，用于六自由度操纵运动方程的测量水动力几乎不存在。第一年，为了弄清这种影响，在大阪州立大学的拖曳水池中，用最大速度为15m/S的高速小车测量了作用于滑行艇模型上的六个水动力分量。该模型完全由六分量称重传感器捕获，其姿态、纵倾、抬高和横倾角是系统的…更多的是改变。试验结果表明，在滑行速度下，水动力与前进速度的平方成正比，姿态对水动力的影响是显著的。第二年，通过对滑行艇1/4缩尺模型进行高速平面运动机构试验，测量了不同平面运动、不同运动姿态、不同升降角下作用于滑行艇模型的六分力。测量数据表明，与受迫运动频率相同的一阶分量明显大于高阶分量。这意味着水动力模型只能用运动速度和加速度的一阶分量来表示。航行姿态对滑行艇水动力系数的影响是非常重要的，这对滑行艇的操纵性是必要的。最后一年，发展了一种模型试验方法--部分捕获PMM试验，用于测量滑行艇周期性操纵运动引起的不稳定运动。对Fn=2.0时滑行艇的试验结果表明，当PMM给出的运动频率与横摇固有频率重合，且与滑行艇升沉固有频率的一半重合时，发生剧烈运动，即大横摇、升沉、纵摇耦合运动。应当注意的是，摇摆运动的频率与PMM给出的强迫运动的频率相同，但垂荡和俯仰运动的频率是强迫运动的两倍。为了弄清剧烈运动的原因，通过对捕获的模型进行PMM试验和倾斜拖曳试验，测量了周期性操纵运动中作用在船体上的水动力。试验结果表明，在高速下，船体的横摇位移产生水动力升沉力和纵倾力矩。利用测得的水动力进行了运动的非线性时间域仿真。模拟的运动与实验结果吻合较好。较少

Very limited numbers of studies on maneuverability of hard-chine planing hulls have been carried out, and any theoretical or experimental procedures to simulate the maneuvering characteristics of them have not been established yet. Although the most important characteristic that is different from that of a conventional displacement vessel seems to be the significant effects of changing of running attitude on maneuvering, measured hydrodynamic forces to use in a motion equations for maneuverability of six-degree-of-freedom for them are almost nonexistent as far as the authors know.In the first year, in order to clarify the effects, a six components of hydrodynamic forces acting on the scale model of a planing craft in oblique towing condition are measured using a high-speed carriage, maximum speed of which is 15m/s, in the towing tank of Osaka Prefecture University. The model is fully captured by a six-component load cell, and its attitudes, trim, rise and heel angle, are systematically … More changed. The experimental results show that the hydrodynamic forces are proportional to the square of advanced speed at planing speed, and demonstrate that the effects of attitude on the hydrodynamic forces are significant. The dependency of each hydrodynamic component on the running attitude is identified on the basis of the experimental results.In the second year, six-component hydrodynamic forces acting on the 1/4 scale model of a planing craft by planar motion mechanism test at high forward speed are measured for various planar motions and running attitudes, rise and trim angle. The measured data show that the first order components with the same frequency as that of forced motion are significantly larger than high order components. This means that the hydrodynamic forces model can be expressed by only the first order components of motion's velocity and acceleration. The effect of running attitudes on the hydrodynamic coefficients is significant and it is necessary for maneuverability of planing craft to take into account this effect.In the final year, a model test method, a partly captured PMM test, to measure unstable motions of a planing crafl induced by periodic maneuvering motion is developed. The experimental results of a planing craft at Fn=2.0 by the method demonstrates that a violent motion which is large rolling, heaving and pitching coupling motion occurs when the frequency of motion given by PMM coincides with the rolling natural frequency, and with the half of the heaving and pitching natural frequency of the craft. It should be noted that the rolling motion has the same frequency as the forced motion given by PMM, but that the heaving and pitching motions have the twice of the frequency of the forced motion. In order to clarify the cause of the violent motion, the hydrodynamic forces acting on the hull in periodic maneuvering motions are measured by PMM tests for a captured model and obliquely towing tests. The experimental results show that the rolling displacement of the craft generates hydrodynamic heaving force and pitching moment at high speed. A non-linear time-domain simulation of the motions using the measured hydrodynamic forces is carried out. The simulated motions are in fairly good agreement with the experimental ones. Less